British officials are concerned about encryption in Microsoft's forthcoming Windows Vista release, saying the technology could prevent law enforcement from reading suspects' computer files. They claim certain new features within Vista, while intended to do good, may actually set back terrorism investigations.

The comments came as part of a larger House of Commons home affairs select committee meeting on holding terrorism suspects. Ross Anderson, professor of security engineering at Cambridge University, said, "from later this year, the encryption landscape is going to change with the release of Microsoft Vista."

Vista will come with a feature called BitLocker, which enables users to encrypt all the data on a system including the OS and boot sector. The idea is to keep data on stolen laptops from being accessed, but it also means it will become "seriously difficult" to read encrypted information off the hard disk, says Anderson.

He suggested that the British government talk with Microsoft and computer vendors assure that there is some type of "backdoor key" in order to allow law enforcement access.

The British government later told BBC News that it was in talks with the Redmond company over the issue.

Microsoft says that BitLocker is intended to preserve system security and "ensures that data stored on a computer running Windows Vista is not revealed if the machine is tampered with when the installed operating system is offline."

The technology will additionally prevent malicious software from being installed on computers without the user's consent.

But the move has been criticized by some, who say companies could use the digital rights management to prevent users from installing programs they have not approved, such as peer-to-peer file sharing applications.